From mboxrd@z Thu Jan 1 00:00:00 1970 From: James Simmons Date: Thu, 27 Feb 2020 16:18:01 -0500 Subject: [lustre-devel] [PATCH 613/622] lustre: osc: glimpse and lock cancel race In-Reply-To: <1582838290-17243-1-git-send-email-jsimmons@infradead.org> References: <1582838290-17243-1-git-send-email-jsimmons@infradead.org> Message-ID: <1582838290-17243-614-git-send-email-jsimmons@infradead.org> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: lustre-devel@lists.lustre.org From: Alexander Zarochentsev osc_dlm_blocking_ast0 clears l_ast_data before writing file data to OST and opens a race window. Neither a glimpse AST nor ldlm_cb_interpret can find correct file attributes at that moment. Cray-bug-id: LUS-8344 WC-bug-id: https://jira.whamcloud.com/browse/LU-13128 Lustre-commit: 7c99f67d9d39 ("LU-13128 osc: glimpse and lock cancel race") Signed-off-by: Alexander Zarochentsev Reviewed-on: https://review.whamcloud.com/37215 Reviewed-by: Andrew Perepechko Reviewed-by: Andriy Skulysh Reviewed-by: Oleg Drokin Signed-off-by: James Simmons --- fs/lustre/include/obd_support.h | 1 + fs/lustre/mdc/mdc_dev.c | 2 +- fs/lustre/osc/osc_lock.c | 8 ++++++-- 3 files changed, 8 insertions(+), 3 deletions(-) diff --git a/fs/lustre/include/obd_support.h b/fs/lustre/include/obd_support.h index 7dfef0f..f7fed0e 100644 --- a/fs/lustre/include/obd_support.h +++ b/fs/lustre/include/obd_support.h @@ -332,6 +332,7 @@ #define OBD_FAIL_OSC_CONNECT_GRANT_PARAM 0x413 #define OBD_FAIL_OSC_DELAY_IO 0x414 #define OBD_FAIL_OSC_NO_SIZE_DATA 0x415 +#define OBD_FAIL_OSC_DELAY_CANCEL 0x416 #define OBD_FAIL_PTLRPC 0x500 #define OBD_FAIL_PTLRPC_ACK 0x501 diff --git a/fs/lustre/mdc/mdc_dev.c b/fs/lustre/mdc/mdc_dev.c index 496491f..5a6be44 100644 --- a/fs/lustre/mdc/mdc_dev.c +++ b/fs/lustre/mdc/mdc_dev.c @@ -313,7 +313,6 @@ static int mdc_dlm_blocking_ast0(const struct lu_env *env, if (dlmlock->l_ast_data) { obj = osc2cl(dlmlock->l_ast_data); - dlmlock->l_ast_data = NULL; cl_object_get(obj); } unlock_res_and_lock(dlmlock); @@ -332,6 +331,7 @@ static int mdc_dlm_blocking_ast0(const struct lu_env *env, */ /* losing a lock, update kms */ lock_res_and_lock(dlmlock); + dlmlock->l_ast_data = NULL; cl_object_attr_lock(obj); attr->cat_kms = 0; cl_object_attr_update(env, obj, attr, CAT_KMS); diff --git a/fs/lustre/osc/osc_lock.c b/fs/lustre/osc/osc_lock.c index ce592d7..3bb5bbd 100644 --- a/fs/lustre/osc/osc_lock.c +++ b/fs/lustre/osc/osc_lock.c @@ -419,13 +419,13 @@ static int __osc_dlm_blocking_ast(const struct lu_env *env, if (dlmlock->l_ast_data) { obj = osc2cl(dlmlock->l_ast_data); - dlmlock->l_ast_data = NULL; - cl_object_get(obj); } unlock_res_and_lock(dlmlock); + OBD_FAIL_TIMEOUT(OBD_FAIL_OSC_DELAY_CANCEL, 5); + /* if l_ast_data is NULL, the dlmlock was enqueued by AGL or * the object has been destroyed. */ @@ -442,6 +442,10 @@ static int __osc_dlm_blocking_ast(const struct lu_env *env, /* losing a lock, update kms */ lock_res_and_lock(dlmlock); + /* clearing l_ast_data after flushing data, + * to let glimpse ast find the lock and the object + */ + dlmlock->l_ast_data = NULL; cl_object_attr_lock(obj); /* Must get the value under the lock to avoid race. */ old_kms = cl2osc(obj)->oo_oinfo->loi_kms; -- 1.8.3.1